Analysis of eukaryotic expression of plasmids. Total RNA was extracted from the liver 7 hours after the injection and the expressions of GM-CSF and mZP3 were detected by RT-PCR. A, lane M, 15 000 + 2000 bp DNA marker; lane 1, p-GM-CSF RNA; lane 2, pVAX cDNA; lane 3, p-GM-CSF cDNA; lane 4, p-GM-CSF plasmid. B, lane M, 5000 bp DNA marker; lane 1, p-mZP3 RNA; lane 2, pVAX cDNA; lane 3, p-mZP3 cDNA; lane 4, p-mZP3 plasmid. RT-PCR indicates reverse transcription–polymerase chain reaction; GM-CSF, granulocyte–macrophage colony-stimulating factor; mZP3, mouse zona pellucida 3; cDNA, complementary DNA.